Answer:
90J
Explanation:
The only time work is being done is when he lifts the box off the ground. Therefore, using the work formula, 2 x 45, you get 90J. Hope this helps someone.
Answer:
The maximum velocity the mass can have if the string is not to break = 29.05 m/s
Explanation:
The force balance in the mass:
The tension in the string must always be equal to the force keeping the mass in horizontal circular motion.
The force keeping the mass in circular motion is given by
F = mv²/r
m = mass of body = 0.4 kg
v = speed of the body in circular motion
r = radius of the circular motion = 0.75 m
Maximum tension the string can withstand will correspond to the maximum velocity of the body in horizontal circular motion
T = F = mv²/r
450 = (0.4)(v²)/(0.75)
v² = 450×0.75/0.4 = 843.75
v = 29.05 m/s
Answer:
the final velocity of the two blocks is 
the distance that A slides relative to B is 
Explanation:
From the diagram below;
acceleration of A relative to B is : 
where
v = u + at
Making t the subject of the formula; we have:
which implies the distance that A slides relative to B.
The final velocities of the two blocks can be determined as follows:
v = u + at
Thus, the final velocity of the two blocks is
Heat<span> capacity ( C ) </span>does change with mass<span>. However, </span>specific heat<span> is the </span>heat<span>capacity per unit </span>mass<span> ( c=Cm ). Therefore if you double the amount of </span>mass<span> in your system, you've doubled its </span>heat<span> capacity, but you've kept the </span>specific heat<span> the same. ... </span>Specific<span> gravity is another such quantity.</span>
Answer:
B, the number of protons.
Explanation:
It is the number of protons found in the nucleus of the atom.
